Xin Yu , Zhen Yang , Zhilan Ma , Ru Yan , Jianzhong Zhang
{"title":"血管紧张素1-7对自发性高血压大鼠肥厚心肌的电生理作用。","authors":"Xin Yu , Zhen Yang , Zhilan Ma , Ru Yan , Jianzhong Zhang","doi":"10.1016/j.mvr.2025.104843","DOIUrl":null,"url":null,"abstract":"<div><div>This study aimed to explore the effects of Angiotensin 1–7 (Ang1–7) on electrophysiological remodeling of hypertensive hypertrophic myocardium in spontaneously hypertensive rats (SHR). Thirty male SHR rats were equally divided into three groups: SHR control group (SHR<img>C) treated with saline; Ang1–7 group (SHR-A) treated with Ang1–7[25 μg·(kg min)<sup>−1</sup>] and Ang1–7 blocker group (SHR<img>B) treated with A779 [72 μg·(kg min)<sup>−1</sup>]. Wistar-Kyoto (WKY) rats (<em>n</em> = 10) were used as a normotensive group. The treatment period was 5 weeks. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured. Echocardiography was used to evaluate cardiac function. The ventricular myocytes were isolated for evaluation of electrophysiological remodeling of myocardium using microelectrode and patch clamp techniques. When compared with those in WKY rats before treatment, systolic and diastolic pressures were significantly higher in SHR (<em>P</em> < 0.01 and <em>P</em> < 0.001 respectively), left ventricular end-diastolic diameter (LVEDd) was significantly lower (<em>P</em> < 0.05), while diastolic interventricular septum thickness (IVSd), diastolic left ventricular posterior wall thickness (LVPWd) were significantly greater in SHR (<em>P</em> < 0.01). After 5 weeks of treatment, compared with SHR-C group, SBP, DBP, IVSd, LVPWd in SHR-A group were lower significantly (<em>P</em> < 0.05), while SBP in SHR-B group was significantly higher (<em>P</em> < 0.05). Compared with WKY group, the resting potential (RP), action potential amplitude (APA) and transient sodium current (<em>I</em><sub>Na-T</sub>) in SHR group were significantly lower (<em>P</em> < 0.05), and the action potential duration (APD<sub>20</sub>, APD<sub>50</sub> and APD<sub>90</sub>) in SHR group was greater (<em>P</em> < 0.05). After Ang1–7 intervention, RP, APA and <em>I</em><sub>Na-T</sub> were significantly greater in SHR-A than those in SHR-C (<em>P</em> < 0.05), and APD in SHR-A significantly lower than that in SHR-C (<em>P</em> < 0.05). Taken together, these results demonstrated that Ang1–7 can not only decrease the blood pressure, but reverse the myocardial hypertrophy and electrophysiological remodeling as well in SHR rats.</div></div>","PeriodicalId":18534,"journal":{"name":"Microvascular research","volume":"161 ","pages":"Article 104843"},"PeriodicalIF":2.7000,"publicationDate":"2025-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"The electrophysiological effects of angiotensin 1–7 on hypertrophic myocardium in spontaneously hypertensive rats\",\"authors\":\"Xin Yu , Zhen Yang , Zhilan Ma , Ru Yan , Jianzhong Zhang\",\"doi\":\"10.1016/j.mvr.2025.104843\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>This study aimed to explore the effects of Angiotensin 1–7 (Ang1–7) on electrophysiological remodeling of hypertensive hypertrophic myocardium in spontaneously hypertensive rats (SHR). Thirty male SHR rats were equally divided into three groups: SHR control group (SHR<img>C) treated with saline; Ang1–7 group (SHR-A) treated with Ang1–7[25 μg·(kg min)<sup>−1</sup>] and Ang1–7 blocker group (SHR<img>B) treated with A779 [72 μg·(kg min)<sup>−1</sup>]. Wistar-Kyoto (WKY) rats (<em>n</em> = 10) were used as a normotensive group. The treatment period was 5 weeks. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured. Echocardiography was used to evaluate cardiac function. The ventricular myocytes were isolated for evaluation of electrophysiological remodeling of myocardium using microelectrode and patch clamp techniques. When compared with those in WKY rats before treatment, systolic and diastolic pressures were significantly higher in SHR (<em>P</em> < 0.01 and <em>P</em> < 0.001 respectively), left ventricular end-diastolic diameter (LVEDd) was significantly lower (<em>P</em> < 0.05), while diastolic interventricular septum thickness (IVSd), diastolic left ventricular posterior wall thickness (LVPWd) were significantly greater in SHR (<em>P</em> < 0.01). After 5 weeks of treatment, compared with SHR-C group, SBP, DBP, IVSd, LVPWd in SHR-A group were lower significantly (<em>P</em> < 0.05), while SBP in SHR-B group was significantly higher (<em>P</em> < 0.05). Compared with WKY group, the resting potential (RP), action potential amplitude (APA) and transient sodium current (<em>I</em><sub>Na-T</sub>) in SHR group were significantly lower (<em>P</em> < 0.05), and the action potential duration (APD<sub>20</sub>, APD<sub>50</sub> and APD<sub>90</sub>) in SHR group was greater (<em>P</em> < 0.05). After Ang1–7 intervention, RP, APA and <em>I</em><sub>Na-T</sub> were significantly greater in SHR-A than those in SHR-C (<em>P</em> < 0.05), and APD in SHR-A significantly lower than that in SHR-C (<em>P</em> < 0.05). Taken together, these results demonstrated that Ang1–7 can not only decrease the blood pressure, but reverse the myocardial hypertrophy and electrophysiological remodeling as well in SHR rats.</div></div>\",\"PeriodicalId\":18534,\"journal\":{\"name\":\"Microvascular research\",\"volume\":\"161 \",\"pages\":\"Article 104843\"},\"PeriodicalIF\":2.7000,\"publicationDate\":\"2025-07-13\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Microvascular research\",\"FirstCategoryId\":\"3\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0026286225000627\",\"RegionNum\":4,\"RegionCategory\":\"医学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"PERIPHERAL VASCULAR DISEASE\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Microvascular research","FirstCategoryId":"3","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0026286225000627","RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"PERIPHERAL VASCULAR DISEASE","Score":null,"Total":0}
The electrophysiological effects of angiotensin 1–7 on hypertrophic myocardium in spontaneously hypertensive rats
This study aimed to explore the effects of Angiotensin 1–7 (Ang1–7) on electrophysiological remodeling of hypertensive hypertrophic myocardium in spontaneously hypertensive rats (SHR). Thirty male SHR rats were equally divided into three groups: SHR control group (SHRC) treated with saline; Ang1–7 group (SHR-A) treated with Ang1–7[25 μg·(kg min)−1] and Ang1–7 blocker group (SHRB) treated with A779 [72 μg·(kg min)−1]. Wistar-Kyoto (WKY) rats (n = 10) were used as a normotensive group. The treatment period was 5 weeks. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured. Echocardiography was used to evaluate cardiac function. The ventricular myocytes were isolated for evaluation of electrophysiological remodeling of myocardium using microelectrode and patch clamp techniques. When compared with those in WKY rats before treatment, systolic and diastolic pressures were significantly higher in SHR (P < 0.01 and P < 0.001 respectively), left ventricular end-diastolic diameter (LVEDd) was significantly lower (P < 0.05), while diastolic interventricular septum thickness (IVSd), diastolic left ventricular posterior wall thickness (LVPWd) were significantly greater in SHR (P < 0.01). After 5 weeks of treatment, compared with SHR-C group, SBP, DBP, IVSd, LVPWd in SHR-A group were lower significantly (P < 0.05), while SBP in SHR-B group was significantly higher (P < 0.05). Compared with WKY group, the resting potential (RP), action potential amplitude (APA) and transient sodium current (INa-T) in SHR group were significantly lower (P < 0.05), and the action potential duration (APD20, APD50 and APD90) in SHR group was greater (P < 0.05). After Ang1–7 intervention, RP, APA and INa-T were significantly greater in SHR-A than those in SHR-C (P < 0.05), and APD in SHR-A significantly lower than that in SHR-C (P < 0.05). Taken together, these results demonstrated that Ang1–7 can not only decrease the blood pressure, but reverse the myocardial hypertrophy and electrophysiological remodeling as well in SHR rats.
期刊介绍:
Microvascular Research is dedicated to the dissemination of fundamental information related to the microvascular field. Full-length articles presenting the results of original research and brief communications are featured.
Research Areas include:
• Angiogenesis
• Biochemistry
• Bioengineering
• Biomathematics
• Biophysics
• Cancer
• Circulatory homeostasis
• Comparative physiology
• Drug delivery
• Neuropharmacology
• Microvascular pathology
• Rheology
• Tissue Engineering.